Associations of viral ribonucleic acid (RNA) shedding patterns with clinical illness and immune responses in Severe Acute Respiratory Syndrome Coronavirus 2 (SARS‐CoV‐2) infection

Abstract

Objectives A wide range of duration of viral RNA shedding in patients infected with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS‐CoV‐2) has been observed. We aimed to investigate factors associated with prolonged and intermittent viral RNA shedding in a retrospective cohort of symptomatic COVID‐19 patients. Methods Demographic, clinical and laboratory data from hospitalised COVID‐19 patients from a single centre with two consecutive negative respiratory reverse transcription‐polymerase chain reaction (RT‐PCR) results were extracted from electronic medical records. Kaplan–Meier survival curve analysis was used to assess the effect of clinical characteristics on the duration and pattern of shedding. Plasma levels of immune mediators were measured using Luminex multiplex microbead‐based immunoassay. Results There were 201 symptomatic patients included. Median age was 49 years (interquartile range 16–61), and 52.2% were male. Median RNA shedding was 14 days (IQR 9–18). Intermittent shedding was observed in 77 (38.3%). We did not identify any factor associated with prolonged or intermittent viral RNA shedding. Duration of shedding was inversely correlated with plasma levels of T‐cell cytokines IL‐1β and IL‐17A at the initial phase of infection, and patients had lower levels of pro‐inflammatory cytokines during intermittent shedding. Conclusions Less active T‐cell responses at the initial phase of infection were associated with prolonged viral RNA shedding, suggesting that early immune responses are beneficial to control viral load and prevent viral RNA shedding. Intermittent shedding is common and may explain re‐detection of viral RNA in recovered patients.

Antibody seroconversion in asymptomatic and symptomatic patients infected with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2)

“…Moreover, most IgG and IgM seroconversion could be observed at the time of virus clearance (Figure 4a). Our results thus support literature findings that seroconversion correlates with the steady decline in viral loads 4 and that early immune responses are beneficial to control SARS‐CoV‐2 36 …”

Lack of viable severe acute respiratory coronavirus virus 2 (SARS-CoV-2) among PCR-positive air samples from hospital rooms and community isolation facilities

“…It is well understood that viral shedding from the respiratory tract of COVID-19 patients tends to peak early in the disease course, 9,10 and results from both our current study and previous pilot study demonstrate our ability to capture aerosolized SARS-CoV-2 from nearby patients with known clinical cycle threshold (Ct) values below 21. 5 Taken together, it is plausible to estimate that the risk of SARS-CoV-2 infection through inhalation is lower when COVID-19 patients are later in their illness and have higher clinical Ct values and SARS-CoV-2 in nearby aerosols is below the detection limit or is not present.…”

“…We hypothesized that infectious SARS-CoV-2 could be isolated from air samples obtained from rooms of patients early in their illness, when viral shedding from the respiratory tract tends to peak. 9,10…”

Seroprevalence of antibodies to SARS-CoV-2 among blood donors in the early months of the pandemic in Saudi Arabia

“…The low prevalence of antibodies might not indicate a true low prevalence of past infection. In a review article ( Tirupathi et al, 2020b ), it was noted that antibody response can decrease in one to three months after acute infection ( Long et al, 2020 , Robbiani et al, 2020 ) and that the level of antibodies, persistence and duration of antibodies may differ among different patients ( Lee et al, 2020 , To et al, 2020 , Xu et al, 2020 ). This overall seroprevalence rate is lower than the rate of 2.36% among healthcare workers in Saudi Arabia ( Alserehi et al, 2020 ).…”